I Chronicles 19:8-19

Now when David heard of it, he sent Joab and all the army of the mighty men. Then the people of Ammon came out and put themselves in battle array before the gate of the city, and the kings who had come were by themselves in the field. When Joab saw that the battle line was against him before and behind, he chose some of Israel’s best and put them in battle array against the Syrians. And the rest of the people he put under the command of Abishai his brother, and they set themselves in battle array against the people of Ammon. Then he said, “If the Syrians are too strong for me, then you shall help me; but if the people of Ammon are too strong for you, then I will help you. Be of good courage, and let us be strong for our people and for the cities of our God. And may the LORD do what is good in His sight.” So Joab and the people who were with him drew near for the battle against the Syrians, and they fled before him. When the people of Ammon saw that the Syrians were fleeing, they also fled before Abishai his brother, and entered the city. So Joab went to Jerusalem. Now when the Syrians saw that they had been defeated by Israel, they sent messengers and brought the Syrians who were beyond the River, and Shophach the commander of Hadadezer’s army went before them. When it was told David, he gathered all Israel, crossed over the Jordan and came upon them, and set up in battle array against them. So when David had set up in battle array against the Syrians, they fought with him. Then the Syrians fled before Israel; and David killed seven thousand charioteers and forty thousand foot soldiers of the Syrians, and killed Shophach the commander of the army. And when the servants of Hadadezer saw that they were defeated by Israel, they made peace with David and became his servants. So the Syrians were not willing to help the people of Ammon anymore.